[gimp] Bug 569550 - Can not handle PSD layers/groups

[Mikael Magnusson <mikachu src gnome org>]

commit ba324c06f54ad351f1fd22193a9a97ea63b08fb1
Author: Dave Lichterman <laviddichterman gmail com>
Date:   Fri Apr 8 02:38:40 2011 -0700

    Bug 569550 - Can not handle PSD layers/groups
    
    Add support to file-psd plugin for layer group reading.

 plug-ins/file-psd/psd-layer-res-load.c |   30 ++++----------
 plug-ins/file-psd/psd-load.c           |   68 +++++++++++++++++++++++++++++--
 plug-ins/file-psd/psd.h                |    5 +-
 3 files changed, 74 insertions(+), 29 deletions(-)
---
diff --git a/plug-ins/file-psd/psd-layer-res-load.c b/plug-ins/file-psd/psd-layer-res-load.c
index 8249c96..f98377f 100644
--- a/plug-ins/file-psd/psd-layer-res-load.c
+++ b/plug-ins/file-psd/psd-layer-res-load.c
@@ -72,8 +72,8 @@
  * Other *
   PSD_LOTH_PATTERN        "Patt"        -       * Patterns (PS6) *
   PSD_LOTH_GRADIENT       "grdm"        -       * Gradient settings (PS6) *
-  PSD_LOTH_SECTION        "lsct"    Drop Layer  * Section divider setting (PS6) (Layer Groups) *
-  PSD_LOTH_RESTRICT       "brst"        -       * Channel blending restirction setting (PS6) *
+  PSD_LOTH_SECTION        "lsct"     Loaded     * Section divider setting (PS6) (Layer Groups) *
+  PSD_LOTH_RESTRICT       "brst"        -       * Channel blending restriction setting (PS6) *
   PSD_LOTH_FOREIGN_FX     "ffxi"        -       * Foreign effect ID (PS6) *
   PSD_LOTH_PATT_DATA      "shpa"        -       * Pattern data (PS6) *
   PSD_LOTH_META_DATA      "shmd"        -       * Meta data setting (PS6) *
@@ -452,8 +452,11 @@ load_resource_lsct (const PSDlayerres  *res_a,
                     FILE               *f,
                     GError            **error)
 {
-  /* Load adjustment layer */
-  static gboolean   msg_flag = FALSE;
+  /* Load layer group & type information
+   * Type 0: not a group
+   * Type 1: Open folder
+   * Type 2: Closed folder
+   * Type 3: End of most recent group */
   guint32           type;
 
   IFDBG(2) g_debug ("Process layer resource block %.4s: Section divider", res_a->key);
@@ -465,24 +468,7 @@ load_resource_lsct (const PSDlayerres  *res_a,
   type = GUINT32_FROM_BE (type);
   IFDBG(3) g_debug ("Section divider type: %i", type);
 
-  if (type == 1 ||      /* Layer group start - open folder */
-      type == 2)        /* Layer group start - closed folder */
-    {
-      lyr_a->drop = TRUE;
-      if (! msg_flag && CONVERSION_WARNINGS)
-        {
-          g_message ("Warning:\n"
-                     "The image file contains layer groups. "
-                     "These are not supported by the GIMP and will "
-                     "be dropped.");
-          msg_flag = TRUE;
-        }
-    }
-
-  if (type == 3)        /* End of layer group - hidden in UI */
-      lyr_a->drop = TRUE;
-
-
+  lyr_a->group_type = type;
   return 0;
 }
 
diff --git a/plug-ins/file-psd/psd-load.c b/plug-ins/file-psd/psd-load.c
index 969a266..3529bae 100644
--- a/plug-ins/file-psd/psd-load.c
+++ b/plug-ins/file-psd/psd-load.c
@@ -531,6 +531,7 @@ read_layer_block (PSDimage  *img_a,
               /* Initialise record */
               lyr_a[lidx]->drop = FALSE;
               lyr_a[lidx]->id = 0;
+              lyr_a[lidx]->group_type = 0;
 
               if (fread (&lyr_a[lidx]->top, 4, 1, f) < 1
                   || fread (&lyr_a[lidx]->left, 4, 1, f) < 1
@@ -1012,6 +1013,8 @@ add_layers (const gint32  image_id,
             GError      **error)
 {
   PSDchannel          **lyr_chn;
+  GArray               *parent_group_stack;
+  gint32                parent_group_id = -1;
   guchar               *pixels;
   guint16               alpha_chn;
   guint16               user_mask_chn;
@@ -1059,6 +1062,10 @@ add_layers (const gint32  image_id,
       return -1;
     }
 
+  /* set the root of the group hierarchy */
+  parent_group_stack = g_array_new (FALSE, FALSE, sizeof(gint32));
+  g_array_append_val (parent_group_stack, parent_group_id);
+
   for (lidx = 0; lidx < img_a->num_layers; ++lidx)
     {
       IFDBG(2) g_debug ("Process Layer No %d.", lidx);
@@ -1079,9 +1086,28 @@ add_layers (const gint32  image_id,
           g_free (lyr_a[lidx]->chn_info);
           g_free (lyr_a[lidx]->name);
         }
-
       else
         {
+          if (lyr_a[lidx]->group_type != 0)
+            {
+              if (lyr_a[lidx]->group_type == 3)
+                {
+                  /* the </Layer group> marker layers are used to
+                     assemble the layer structure in a single pass */
+                  layer_id = gimp_layer_group_new (image_id);
+                }
+              else /* group-type == 1 || group_type == 2 */
+                {
+                  layer_id = g_array_index (parent_group_stack, gint32,
+                                            parent_group_stack->len-1);
+                  /* since the layers are stored in reverse, the group
+                     layer start marker actually means we're done with
+                     that layer group */
+                  g_array_remove_index (parent_group_stack,
+                                        parent_group_stack->len-1);
+                }
+            }
+
           /* Empty layer */
           if (lyr_a[lidx]->bottom - lyr_a[lidx]->top == 0
               || lyr_a[lidx]->right - lyr_a[lidx]->left == 0)
@@ -1221,6 +1247,8 @@ add_layers (const gint32  image_id,
           l_y = 0;
           l_w = img_a->columns;
           l_h = img_a->rows;
+          parent_group_id = g_array_index (parent_group_stack, gint32,
+                                           parent_group_stack->len-1);
 
           IFDBG(3) g_debug ("Re-hash channel indices");
           for (cidx = 0; cidx < lyr_a[lidx]->num_channels; ++cidx)
@@ -1247,7 +1275,36 @@ add_layers (const gint32  image_id,
               layer_channels++;
             }
 
-          if (empty)
+          if (lyr_a[lidx]->group_type != 0)
+            {
+              if (lyr_a[lidx]->group_type == 3)
+                {
+                  IFDBG(2) g_debug ("Create placeholder group layer");
+                  g_free (lyr_a[lidx]->name);
+                  gimp_image_insert_layer (image_id, layer_id, parent_group_id, 0);
+                  /* add this group layer as the new parent */
+                  g_array_append_val (parent_group_stack, layer_id);
+                }
+              else
+                {
+                  IFDBG(2) g_debug ("End group layer id %d.", layer_id);
+                  drawable = gimp_drawable_get (layer_id);
+                  layer_mode = psd_to_gimp_blend_mode (lyr_a[lidx]->blend_mode);
+                  gimp_layer_set_mode (layer_id, layer_mode);
+                  gimp_layer_set_opacity (layer_id, 
+                                          lyr_a[lidx]->opacity * 100 / 255);
+                  gimp_item_set_name (drawable->drawable_id, lyr_a[lidx]->name);
+                  g_free (lyr_a[lidx]->name);
+                  gimp_item_set_visible (drawable->drawable_id,
+                                         lyr_a[lidx]->layer_flags.visible);
+                  if (lyr_a[lidx]->id)
+                    gimp_item_set_tattoo (drawable->drawable_id,
+                                          lyr_a[lidx]->id);
+                  gimp_drawable_flush (drawable);
+                  gimp_drawable_detach (drawable);
+                }
+            }
+          else if (empty)
             {
               IFDBG(2) g_debug ("Create blank layer");
               image_type = get_gimp_image_type (img_a->base_type, TRUE);
@@ -1255,7 +1312,7 @@ add_layers (const gint32  image_id,
                                          img_a->columns, img_a->rows,
                                          image_type, 0, GIMP_NORMAL_MODE);
               g_free (lyr_a[lidx]->name);
-              gimp_image_insert_layer (image_id, layer_id, -1, -1);
+              gimp_image_insert_layer (image_id, layer_id, parent_group_id, -1);
               drawable = gimp_drawable_get (layer_id);
               gimp_drawable_fill (drawable->drawable_id, GIMP_TRANSPARENT_FILL);
               gimp_item_set_visible (drawable->drawable_id, lyr_a[lidx]->layer_flags.visible);
@@ -1292,7 +1349,7 @@ add_layers (const gint32  image_id,
                                          layer_mode);
               IFDBG(3) g_debug ("Layer tattoo: %d", layer_id);
               g_free (lyr_a[lidx]->name);
-              gimp_image_insert_layer (image_id, layer_id, -1, -1);
+              gimp_image_insert_layer (image_id, layer_id, parent_group_id, -1);
               gimp_layer_set_offsets (layer_id, l_x, l_y);
               gimp_layer_set_lock_alpha  (layer_id, lyr_a[lidx]->layer_flags.trans_prot);
               drawable = gimp_drawable_get (layer_id);
@@ -1309,7 +1366,7 @@ add_layers (const gint32  image_id,
             }
 
           /* Layer mask */
-          if (user_mask)
+          if (user_mask && lyr_a[lidx]->group_type == 0)
             {
               if (empty_mask)
                 {
@@ -1421,6 +1478,7 @@ add_layers (const gint32  image_id,
       g_free (lyr_a[lidx]);
     }
   g_free (lyr_a);
+  g_array_free (parent_group_stack, FALSE);
 
   return 0;
 }
diff --git a/plug-ins/file-psd/psd.h b/plug-ins/file-psd/psd.h
index e07c7b6..926c349 100644
--- a/plug-ins/file-psd/psd.h
+++ b/plug-ins/file-psd/psd.h
@@ -115,10 +115,10 @@
 #define PSD_LPAR_ANNOTATE       "Anno"          /* Annotation (PS6) */
 
 /* Other */
-#define PSD_LOTH_SECTION        "lsct"          /* Section divider setting - Layer goups (PS6) */
+#define PSD_LOTH_SECTION        "lsct"          /* Section divider setting - Layer groups (PS6) */
 #define PSD_LOTH_PATTERN        "Patt"          /* Patterns (PS6) */
 #define PSD_LOTH_GRADIENT       "grdm"          /* Gradient settings (PS6) */
-#define PSD_LOTH_RESTRICT       "brst"          /* Channel blending restirction setting (PS6) */
+#define PSD_LOTH_RESTRICT       "brst"          /* Channel blending restriction setting (PS6) */
 #define PSD_LOTH_FOREIGN_FX     "ffxi"          /* Foreign effect ID (PS6) */
 #define PSD_LOTH_PATT_DATA      "shpa"          /* Pattern data (PS6) */
 #define PSD_LOTH_META_DATA      "shmd"          /* Meta data setting (PS6) */
@@ -490,6 +490,7 @@ typedef struct
   LayerMaskExtra        layer_mask_extra;       /* Layer mask extra data */
   LayerFlags            layer_flags;            /* Layer flags */
   guint32               id;                     /* Layer ID (Tattoo) */
+  guchar                group_type;             /* 0 -> not a group; 1 -> open folder; 2 -> closed folder; 3 -> end of group */
 } PSDlayer;
 
 /* PSD Channel data structure */